After a Naming Contest, Cardea Joins the Celestial Ranks as a Quasi-Moon

For thousands of years, Cardea has been known as the Roman goddess of doorways and transitions, a guardian of thresholds. On Monday, she joined the celestial ranks of fellow mythological figures like Mars, Venus and Andromeda.

But Cardea is not a planet or a constellation. She is as a quasi-moon — a very-real type of asteroid that appears to be doing a special orbital dance around Earth.

The International Astronomical Union, the organization of scientists charged with awarding official names to space objects, selected Cardea through a naming contest that generated more than 2,700 entries. The winning name was submitted by Clayton Chilcutt, 19, a sophomore from the University of Georgia, who participated in the contest as part of an extra credit assignment in an introductory astronomy class.

“I came across Cardea, and when you read the description, it just sounds celestial,” said Mr. Chilcutt, an accounting and finance major, adding that his “small contribution to science” was now part of the history books.

But after further research, Mr. Nasser, who has a Ph.D. in the history of science from Harvard, learned that the fleck on the poster designated a moon was not technically a moon, but also not not a moon, as he describes it.

A planet orbits around a star, and a moon orbits around a planet. Quasi-moons orbit the sun but are close enough to planets to seem like tiny moons “doing this double Hula-Hoop dance out in space,” Mr. Nasser said.

Mr. Nasser also learned that Zoozve’s real name was not the pile of consonants but simply a misinterpretation from the poster’s artist: Zoozve was actually 2002-VE. Still, he convinced the astronomical union, which usually approves only mythological names from culture or literature, to give 2002-VE the name Zoozve.

“It was totally shocking and it felt like a little coup, like a little nudge for silliness in the universe,” Mr. Nasser said.

But Zoozve was not alone. In fact, Earth had a handful of quasi-moons, too, that were eligible to be named (only one had a non-alphanumeric designation, Kamo’oalewa).

“Nobody seemed to care!” Mr. Nasser said. “We care, I care, a lot of people would care.”

So in June, “Radiolab” and the astronomers union teamed up to find a mythological name befitting of 2004 GU9, a quasi-moon that was discovered in 2004 by the LINEAR project in Socorro, N.M. The astronomical union said one of its closest approaches to Earth will be in October 2026, when it’s about 18.5 million miles from Earth.

The contest solicited names from more than 100 different countries. Many entrants wrote moving tales of mythological origin stories, some from their own cultures and others from oceans away, and what a name like this would mean to the world. The astronomer’s union weeded out duplicates, names already in use and “clearly not mythological names where people didn’t even try,” Mr. Nasser said, like Mooney McMoonface.

“Radiolab” helped assemble a star-studded panel of astronomers, journalists, teachers, students and even a few celebrity nerds, including Bill Nye, Penn Badgley and Celia Rose Gooding. The panelists whittled the list down to seven finalists — two of which came from the same University of Georgia course — and then released the list to the public.

Other finalists included Bakunawa, a mythical dragon from Philippine folklore, who was said to rise from the ocean to swallow the moon; Ehaema, or “Mother Twilight” in Estonian folklore; and Tecciztecatl, an Aztec lunar god who once aspired to be the sun.

“It really brings people into the science who otherwise have been like, ‘Nah, that’s not for me,’” said Kelly Blumenthal, the director of astronomy outreach for the international group.

Ms. Blumenthal said it would “be a shame” to let the other finalists go to waste, and that the union’s naming group will suggest they be used in the future.

For Mr. Nasser, Cardea, the winning name, was ultimately fitting for a quasi-moon: An ancient doorkeeper and protector, a body to watch out for us during a time of tumult and transition.

Mr. Nasser hoped the naming contest helped people feel “feel this connection to what’s bigger than all the chaos that’s happening on the ground right now,” he said. “Space is the biggest big picture we have.”